This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Autism is a severe neurodevelopmental disorder affecting 60/10,000 individuals in the US. It is characterized by social communication deficits and restrictive interests/repetitive behaviors. There is accumulating evidence that oxytocin, produced by the hypothalamus, plays a key role in social cognition and attachment, repetitive behaviors and anxiety. Based on such data, we hypothesize that abnormalities in the oxytocin system may be responsible for some of the core and associated deficits seen in autism. In this study, we will try to assess the effect of IN oxytocin on core and associated symptoms of autism. Twenty adults will be randomized to placebo or active medication in a 1:1 fashion. They will receive 24 IU of oxytocin /placebo in the morning at and noon for 6 weeks. The effect of oxytocin vs. placebo will be assessed using measures of social cognition, repetitive behaviors, irritability, and anxiety. This study will also employ event related recordings (ECRs) to collect naturalistic data on some of the above symptom domains. An additional part of this study will examine the effects of oxytocin on gene expression. Aims - Hypothesis: 1. To investigate the use of intranasal oxytocin as a treatment for autism spectrum disorders; 2. To explore Event Contingent Recording (ECR) to assess changes in mood and social functioning over the course of treatment in adults with autism spectrum disorders;and 3. To perform gene expression profiling using fresh whole blood to explore the molecular mechanisms underlying oxytocin therapy and oxytocin efficacy in adults with high functioning autism or Asperger's syndrome.